Biofilms

When most people think about bacteria, they picture free-swimming, single-celled organisms. In nature, however, most microorganisms form surface-adherent communities known as biofilms. Forming a biofilm is a literally life-changing experience. A film's members embed themselves in a slimy matrix and take on varied roles: Some patrol the perimeter, while "persister cells" go dormant but can revive and reproduce after an antibiotic attack. A biofilm thus offers protection from changes in the environment and antimicrobial substances. Biofilms have an immense impact in natural, medical and agricultural settings.